OBJECTIVES are: 1) To continue our investigation of two clinical groups of children, namely those with identical overt symptoms and those under the impact of identical, potentially pathogenic influences. 2) To continue to test the hypothesis that identical manifest symptoms can stem from a variety of underlying causes and that, conversely, identical pathological processes can give rise to a variety of widely different symptoms. 3) To test the further hypothesis that there are two distinct ways in which children may show divergence from normal progressive development. The first of these, best known from psychoanalytic studies, leads to symptoms based on conflicts which are solved by compromise formations. Such conflicts arise at the earliest ages between the child's whole self and the environment, and at a later stage between the child's drives and his higher intellectual, emotional, and moral functions - in short, within the child's personality structure itself. The second group of childhood abnormalities may prove to be rooted in the developmental processes themselves, that is, in the delays or arrests within, or deviations from, the developmental lines which lead from the infant's immaturity towards the mature functioning of the adult individual.